Tech Notes on Gas Chromatography
by À _>WEI?OGI?APM
Methyl Ricinoleate CONDITIONS AEROGRAPH A-1 IOC SIZE 0.5 Lambda ΓΠΙΙΙΜΝ 2-5 Craig COLUMN s u c c i n a t e TEMPERATURE 240° C. GAS FLOW 50 ml/mm
Lower trace made by Disc integrator quickly gives composition of mixture.
Resolved in 7 minutes! Actually this was a conservative experiment. We resolved methyl ricinoleate in slightly over 7 minutes, but we were just loafing. We could do it in half the time, simply by upping the gas flow to 100ml/ min. This experiment encouraged us to test esters to C-30 and cholesterol. Results will be in the fall issue of Aerograph Research Notes. Write for your free subscription now. Incidentally, we're using a standard model Aerograph A-l 10-C for these separations. So are many other research chemists. While we're doing this work, send us your high molecular weight sample for a free analysis. We'll mail you a chart and a report of results.
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ANALYTICAL CHEMISTRY
REPORT Heavy Workloads in Laboratories
The Division of Technical Services has a headquarters staff of six and a field staff of 125. This number has remained practically constant for the past several years. Since 1955, however, the number of samples handled by the laboratories has increased steadily. The 1958 total of 121,401 is approximately 20% greater than in 1955 when the total was 99,467 (Table I ) . There are thousands of different kinds of imported merchandise which require customs laboratory analysis. For purposes of convenience, these are grouped into 30 different classes. The classes which occur most frequently are ores and minerals, 2 1 % ; soaps, detergents, etc., 15%; fertilizers, seeds, feeds, grains, etc., 9% ; metals and metal products, 7%; and wool, 5% (Tabic Π). In addition to "import" samples, there arc other categories. Almost 4000 samples, for example, represent seizures of narcotic drugs and other prohibited articles. Another 2660 are samples tested for other government agencies. Preshipment samples of new types of merchandise totaled 1402. These were submitted so that facts could be de veloped on which to establish a tariff classification. A small number, 29, were samples of materials imported, processed, and later exported. To ascertain whether critical and strategic items purchased for the na tional stockpile met contract specifica tions, the laboratories analyzed 1962 samples. These included metals, ores, chemicals, drugs, and oils purchased by the General Services Administration. An additional 1962 samples were ex amined for the Federal Supply Service. The workload of the laboratories in cludes many activities not in the cate gory of "samples." Development of new methods and modernization of old ones are examples. Consultation serv ices to customs offices and on-the-job training also do not appear in statisti cal tables of accomplishments. Ap pearances in court as expert witnesses are also time-consuming. In 1958, for example, a total of 24,430 man-hours was spent in such activities.
References
(1) Alves, H. L., "History of Customs Laboratory Activities," Bureau of Customs, July 1953. (2) Parks, A. F., "Technical Informa tion of the U. S. Customs Services," Bureau of Customs, ANAL. C H E M .
27, 19A, (May 1955); p. 11A, (June 1955).
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